a cooperative venture with
Climate Energy LLC
of Massachusettsto produce a "micro-cogenerator"
) based on a Honda engine (hat tips:
Green Car Congress
Peak Oil Optimist
- 85% overall efficiency.
- 1 kW electric output.
- 3 kW heat output.
I make that about 21% electric efficiency and 64% heating efficiency
Poster Gene DeJoannis at
notes that 3 kW of heat is only about 10 kBTU/hr, which
is not enough to supply the peak winter heating requirements of a small
row house, let alone a single-family home. It follows from this that
the cogenerator is not capable of functioning as a stand-alone heating
system; it would require extra heat. The concept is that
the engine runs
, and heat requirements beyond the CHP system are
provided by a conventional combustion boiler. This is included in
. (These graphics answer some questions regarding the
odd-looking cogenerator efficiency numbers; it appears that the cogen
exhaust does not allow recovery of the latent heat of the water vapor
and is also a separate unit from the air handler; as a consequence,
heat losses are higher from the cogenerator side than the backup
furnace.) It also appears that the full heat demand of a house
can be met by the pair, and that the $8000 cost of the two units covers
the entire heating plant. Earlier, I had objected that a $8000
capital expense is very hard to pay off with a $600/year revenue
stream; it appears that the incremental cost of the cogenerator over a
conventional furnace is considerably smaller, and the payoff quicker.
The stated purpose of this cogen is to meet the average electrical
demand of the typical house, without generating surplus power to feed
the grid. I believe that this is a mistake:
- This choice requires the utility to handle the difference between
base-load and peak requirements. It would be trivial to trade
off heating duties between a bigger cogenerator and the furnace section
to approximate the daily demand curve and smooth the load at the
utility. Instead, the cost of winter peaking is put where it's the
most expensive (and least efficient) to meet it.
- The design removes most capability of generation for backup power.
- The design foregoes the capability of generation for other loads,
such as charging electric cars. In other words, it's not designed
with the future in mind.
IMHO, a properly-designed system would be able to handle contingencies.
If the generator was capable of 3 kW and 30,000 BTU/hr, it could supply
a 1 kW average electric load by operating at a 1/3 duty cycle. It
would also be able to crank up to full output and 30,000 BTU/hr to handle
cold snaps, and help to feed the heat pump of the house down the block.
When the homeowner came home with a
or the like,
the system could be programmed (perhaps via a Bluetooth or WiFi connection)
to react to the car plugging in and boost generation to charge it on
power from natural gas instead of oil.
But this isn't going to happen, because it's just too small. The
This one looks like it's under the limit. It needs to grow some;
throw it back.
The low efficiency is a disappointment too.
Cummins claims BSFC as low as 0.32 lbm/hp-hr for some of their diesels; assuming #2 diesel at
19,110 BTU/lbm this works out to over 41% thermal efficiency (and that's the higher
heating value to boot). It ought to be possible to achieve much better than 21%
efficiency from a gas-fired reciprocating engine; perhaps this requires the freedom to begin
with a clean sheet of paper.
I listened to Bush's press conference last night with a growing sense
of frustration and irritation. Does the man know nothing? Is
he unable to see how his own policies have accelerated us to the crisis we
now face? Or is he just a sociopath like Clinton, able to say
whatever serves his immediate purpose with all apparent
sincerity? Regardless, what he said wasn't right; to the extent
that it wasn't irrelevant, it was some of the worst political posturing
I've listened to since Clinton's talk about firearms and interns.
One comment that really got to me was Bush's anecdote of the soldier
who asked him to lower the price of gasoline. Bush's response was
that this was beyond his abilities. Well, of course it is...
now. But was it always? Had I been there and able to
interrupt, I would have had to ask "Mr. President, the high price of
gasoline is due to high world demand for oil and an excess of gasoline
demand over refining capacity in the USA. We used to have programs
to do something about that. But didn't you cancel the Partnership for
a New Generation of Vehicles, and didn't you sign tax breaks which
encouraged people to buy gas-guzzling trucks for business use whether
they needed them or not?"
Among Bush's first acts in office, he cancelled a program which was
ready to produce highly economical vehicles in the very near term; he
substituted a hydrogen-vehicle program which is still unlikely to yield
products before 2015 and will require tens or hundreds of billions in new
infrastructure to support. The first-year tax writeoff for vehicles
over 6500 pounds used in a business helped to run up gasoline demand,
creating windfall profits for gasoline refiners. He also funneled
a bunch of research money to the auto companies for the long term.
Was it worth it? Here's what we lost:
- Valuable capacity margins in fuel refining.
- A better situation with regard to foreign exchange.
- An American hybrid program which would have been market-ready by now.
- Domestic vehicles ready to be converted to
- A ready response to high world oil prices.
- Product lines at domestic manufacturers ready for the shift in consumer demand.
We should be so much further along than we are. PNGV vehicles like
were delivering 72 MPG back
in 2000. The diesel engines might not have met new EPA NOx standards,
but so what? Even if they had to be powered with gasoline engines and
some of the more expensive technologies had to be left off, it is hard to
see how the ESX3 and its like could have achieved less than 50 MPG. With
the addition of removable battery packs, such cars could have operated entirely
on grid power for short trips while maintaining their cargo capacity and
highway fuel economy;
with the Toyota Prius
have shown that this can
be done by dedicated amateurs. But they've got to buy Japanese cars
to do it, because Bush decided that his predecessor's program wasn't
Bush's idea of an energy policy seems to be to:
- Meet with the Saudi oil minister and ask him to pump more oil;
- Hand out lots of subsidies and tax breaks to existing producers;
- Throw money at farmers and ADM (but producing little new energy)
through ethanol and biodiesel subsidies.
None of these initiatives affects anything where the rubber meets the
road. None of them are going to do anything for the budget deficit
or our balance of trade. Arguably, none of them are going to improve
our situation; they are just going to create financial empires based on
Bush ought to have expertise in the oil business. He ought to have
seen all of this coming; he certainly knew the right people to ask for
advice (and if he didn't, Cheney did). He should have known what
programs should have been kept on the back burner for the sake of the
nation and our domestic industries. He was only too happy to use
largesse (e.g. tariff barriers on steel) to buy votes, but he could have
made it go much farther with some statesmanlike vision.
We didn't get it. What we got instead appears to be programs
designed for the benefit of a favored investor/CEO class and the very
foreign oil interests who are waging religious war against us.
This isn't leadership. Neither is it patriotism. And when
the American people figure this out (probably about the time the Democrats
break with the forces of P.C. and get serious about national security),
there's going to be some mighty big scores settled in Washington.
Either that, or the USA becomes one more banana republic.
Ethanol from corn appears to be a loss,
A recent paper
claims that it's bad for just about
everything it touches. Corn (maize) is planted, cultivated, sprayed
and harvested with petroleum products, fertilized with nitrogen fixed using
natural gas, and the ethanol product is distilled using more natural gas
or petroleum-derived propane. This does nothing for our security;
due to the cost of natural gas,
our nitrogen fertilizer is now imported
. The only purpose
served by these subsidies is to transfer
taxpayer dollars to the pockets of those chemical producers and agribusiness
interests like ADM, with a little trickling down to the farmers almost by
accident. If Bush wanted to cut the price of gasoline, he could
push to eliminate the use of ethanol in gasoline and pay farmers to idle
some of their acreage instead; all the fuel the farmers are using on that
idled land would make motorists happier. And that
done in time for this year.
I've been reluctant to talk much about nuclear power here at The
Ergosphere because it's such a politically-charged topic. The
various issues of fuel availability, waste disposal and vulnerability of
reactors to attack attract a great deal of argument with little
agreement even on premises, let alone conclusions. This makes it a
singularly unfruitful area for discussion; it generates a lot of heat
but precious little light.
It might be more fruitful if some of the issues could be taken off
the table. Two of these issues are vulnerability of reactors to
terrorist attack and likelihood of leaks from other accidents.
Reactors are large, stationary (albeit fairly hard) targets; if the same
countermeasures could essentially eliminate the ability of terrorists
to hit the reactor while also confining most conceivable radioactive
accidents to the immediate area, both the real and perceived risks of
nuclear power would be greatly reduced.
One speculative vulnerability of reactors is aerial or artillery
attack, to breach the containment building and rupture the reactor
vessel to cause a meltdown. Leaving aside the extreme difficulty
of getting several bombers or a howitzer into the country and to the
proper position for attack, it's obvious that neither of these attacks
are even possible unless the reactor is above ground. An
underground installation is completely immune from attack by artillery
and would require nuclear bombs to damage with an aerial attack; a
terrorist attacker with a nuke has much better and softer targets than
reactors. It appears that underground construction (at an adequate
depth) is sufficient to eliminate most direct modes of terrorist attack.
The main issue with any such thing is the cost. Mining costs
money, construction in confined spaces is more difficult and expensive
than in open air, and engineering has to be done differently (and thus
separately) for structures intended to go underground. This would
make underground nuclear installations more expensive to build than
aboveground ones. But, I ask, are there compensatory benefits?
I can think of a few:
- There should be few issues with off-site liability insurance.
- Decommissioning means removing the fuel and locking the doors
(well, pouring concrete in the tunnels).
- As isolation is achieved with a physical barrier rather than
distance, plants can be located close to the points of use.
- Transmission losses are reduced.
- Plant waste heat can be used productively.
That last is the big one. If the typical plant is a pebble-bed
HTGR with a conversion efficiency of 40%, it increases the useful energy
from the plant by 150%.
District heating was once commonplace in cities, and the heat came
from the low-pressure steam output of generation plants (this is still
in use in some places, including many university campuses).
Unfortunately, the effort to remove pollution sources from cities also
caused all the byproduct heat to have to be dumped as waste, as heat
cannot be transported long distances without unacceptable cost and
losses. There is now an opportunity to reverse this trend and
capture that waste energy. But what's the value, and is it enough
to pay the extra costs?
Assume for the moment that the new reactors are 400 megawatt
pebble-bed HTGR's, the thermal efficiency is 40%, and T&D losses
for the typical above-ground unit are the average 7%. Further
asssume that the T&D losses for the underground unit are 3%, and
heat losses are 10%. The net product looks like this:
|Net to user
The ability to deliver "waste" heat in this case more than doubles the
total usable output from the plant. But the question still has
not been answered: what's the value of this new product?
The big answer depends on a bunch of smaller questions:
- How much of the rated heat output of the plant is used?
- What energy source is it replacing?
- In what form is it delivered?
- What is the cost of delivery?
- What is the backup in case of interruption?
For the sake of discussion I'll propose numbers that are not researched
and I hope aren't too unrealistic:
- Customers use 60 percent of rated output heat (the plant may
produce less than full output at times of low demand).
- This replaces natural gas for space heat and DHW, as well as
electricity for air conditioning (via absorption chillers).
- Heat is delivered as hot water or low-pressure steam at ~100 C.
- For a wild-assed guess, cost of delivery is 1 cent/kWh.
- The backup is electric resistance heat (used to supply service
when steam/water delivery is interrupted). Note that this is
better than current gas service, which provides no backup.
The retail price of natural gas is unlikely to go below $7/million BTU
in the next few years; if used at 95% efficiency, this corresponds to a
price of 2.5 cents/kWh of heat. The net value of the heat
delivered is the difference between this and the delivery cost, or 1.5
cents/kWh. For absorption A/C the energy replaced is electricity
rather than heat. The real cost of on-peak electricity for A/C is
at least 15 cents/kWh and sometimes much higher, so for this example I
will assume a flat 20 cent rate. The coefficient of performance
(CoP) of a good vapor-compression air conditioner is around 4, and the
CoP of an ammonia-water absorption-cycle chiller is approximately 0.5;
it takes about 8 kWh of heat to displace 1 kWh of electricity for
cooling, so the displaced cost of heat used for cooling is about
2.5 cents/kWh of heat (again).
|Net to user,
| Net value
| Net value
|| 0.4 (heating)
The total net value delivered is $42.6 million/year, or $106.50 per
kilowatt of electric capacity per year.
If natural gas goes up to $10/million BTU, the cost of heat from gas
goes up to 3.6 cents/kWh and the situation looks even better:
|Net to user,
| Net value
| Net value
|| 0.4 (heating)
The total net value delivered nearly doubles to $82.2 million/year, or
What kind of investment does this justify?
I'm no financial expert, but interest rates are fairly low at the
moment. If the investment in heat delivery infrastructure is
financed at 6% and amortized over 30 years, the heat stream is worth
about $1470/kWe at the $7/mmBTU cost of gas and a whopping $2830/kWe at
the $10/mmBTU price of gas! In contrast, the cost of
mass-produced pebble-bed reactors is
estimated at $1000/kWe
. It appears that the ability to make
use of plant waste heat is worth doubling or even tripling the cost of
What would it look like?
From the surface, not much; probably an access tunnel from a building
in an industrial or office park. During construction there would
be a lot of trucks taking soil and rock away and delivering concrete
and other materials. Cables would come to the surface in one or
more places to transmit power to electrical substations.
Underground it would be more interesting. The reactor proper
would lie at a safe (and perhaps considerable) depth, and its main
power turbines would be sited with it. But the heat distribution
network would radiate outward from it like a starburst, with pipes
carrying medium-pressure steam upward to local pressure-drop recovery
turbines in neighborhood manholes feeding the local steam/hot water
distribution pipes. Instead of a gas pipe coming into the house,
there would be a steam/HW supply pipe and a return pipe.
One curious feature is that the heat-distribution system would require
no pumps. Water coming down from the surface would arrive at a
depth of 1000 feet under more than 400 psi of pressure from gravity
alone; this pressure would have to be relieved through a throttling
valve or turbine to reduce it enough for the water to boil at less than
oven temperatures. Low-pressure steam has very low density, which
requires pipes too big to run long distances; the distribution network
would probably use steam at a moderate temperature and pressure.
Medium-pressure steam is far less dense than water, and would arrive at
the surface at not much less pressure than it left the underground; the
pressure could be used to drive another turbine. This convective
loop could generate power and provide fail-proof circulation.
Hardware at buildings would change too. Instead of a furnace,
you'd have a fan coil heated by steam or hot water; instead of a
boiler, you'd have a simple heat exhanger (with backup resistance
element). The water heater would look like an electric, but with
a water/steam coil in the bottom. But the big difference would be
in air condtioning systems. Absorption systems would be larger
than compressors, and would need to reject almost 3 times as much heat;
the outdoor units would be quite a bit larger than present compressors.
It might be worth putting them partially underground, leaving
only the condenser coils in the air. It might also be worth
installing the condensers in thermal chimneys, to cool them with
convective airflow and eliminate the need for fans. This would
have a definite and distinctive architectural impact.
Given such a heat distribution network, the reactor would not need
conventional cooling towers. The A/C chimney systems could be
employed as heat dumps when supply ran beyond demand.
Depending on the reactor design, the potential for damage or failure
seems very small.
- Pebble-bed reactors cannot melt down.
- Deeply buried reactors cannot be hit by aircraft, bombs or
- Gas-cooled reactors are unlikely to transfer radioactive
materials to cooling water or steam.
- Physical isolation of the reactor reduces or eliminates most
Worth doing? Depends what it costs to build something in a mine,
dig miles of tunnels and lay new piping networks. But if it is,
entire cities could be made independent of oil, coal and natural gas
for all their heating, cooling and electric requirements and do it
cleanly and quietly.
That's my kind of solution.
Reps. Fred Upton (R-MI) and Ed Markey (D-MA) have co-sponsored a measure to extend Daylight Saving Time by 2 months
(hat tip: Enviropundit
). The alleged benefit is a savings of 10,000 barrels of oil per day.
US oil consumption is about 20 million barrels per day. The alleged benefits amount to one twentieth of one percent. Why are they wasting their time and issuing press releases on what amounts to Trivial Pursuit? Is this what their constitutents sent them to Washington for? Have they nothing better to do
Those two should withdraw their bill and start over. If they wanted to make a real difference, their bill should require that, by 2010, 50% of all passenger cars and light trucks sold in the USA must be able to travel 20 miles at 55 MPH on electricity alone, no liquid fuel allowed (the Prius Plus program
has shown how easy this is to do). This bill should also immediately return depreciation schedules for all business vehicles to normal at the same time... retroactively for all the doctors, lawyers and other people who bought huge trucks as status symbols instead of business necessities. That would do something about our budget deficit too.
Everybody has biases. The Republicans have biases. The
Democrats have biases. Oil and coal company executives are
biased. Environmentalists are biased. The P.C. contingent
[spit] on the campus of my alma mater will deny they are biased
because "multi-culturalists make no judgements and cannot be biased",
but that in itself is a bias against the values of the majority society.
I'm biased. There, that's out of the way.
There are differences between biases. One can have biases
which are based on (ranked from noble to ignoble) honest disagreement
about the meaning of the facts, ignorance, or disregard for the facts.
The biases one carries are part and parcel of where one stands in the
various conflicts in life: which side you're on.
Biases can be overt. I hope I've been honest if not
completely explicit about my biases against
foolishness like perverse incentives and counterproductive subsidies,
dependence on foreign oil and our gas-pump financing of radical Islam, and
efficiency, nuclear power, alternative energy where appropriate,
and better ways of doing things in general. If you've missed this
before, here it is; if you see me appearing to argue contrary to one
of my positions above it's almost certainly because the devil is in
the details and it's often very easy to miss one little thing and get
the big thing badly wrong. (See CAFE
Hidden biases are another thing. They are one of the
trademarks of propaganda, and are often used to mislead. They
come in a dozen styles, but one is to gloss over or ignore facts which
would lead others away from the propagandist's desired conclusion.
The desired conclusion may be one to compel action where none is desirable
or warranted; contrarily, the desired conclusion may be that action is
futile, inducing paralysis in the believers when something can and ought
to be done.
Which brings me to the
most recent newsletter
of the Association for the Study of Peak
("Life after oil", article #524, pp. 7-9). This
piece, excerpted by C.J. Campbell, appears to be largely taken from a
2003 book by William Stanton; it paints a future of England in 2050
which is powered by biomass in the form of wood. According to the
author, the maintenance of a "passable standard of living" would require
about 230 tons of wood per person per year. The resulting economic
and social organization would yield a lifestyle which is "attractive for
Survivors, you say? Yes, survivors. How many survivors?
About 2 million: one-third of England's population in 1750, and one
thirtieth of the population today. Consider this carefully: if
one quarter of England's current population is now under the age of 20,
of those people will have to be gone before
the age of 65 for the population to drop to 2 million. The alternatives:
leave the country (for where?) or die. And there could be no births
in the whole country for the next forty-five years, because for each baby
somebody else would have to go.
The transition to a peaceful, stable and sustainable society would have
to be done carefully. A smooth evolution is essential; serious
instability would destroy many of the resources that the future economy
would depend on. Does anyone in their right mind think that
eighty-seven percent of the population is going to accept deportation or
early demise quietly? Can anyone believe that the kind of crisis (like
a plague) which could do this without explicit violence would leave much
behind? Yet this kind of mess is left, implied but unstated, in
What conclusion is the reader supposed to draw? How about "Oh my
god, sustainable society is just code for MASS DEATH! We can't even
think of going down that path!" Or, "We can't live through the
changes coming. Eat, drink and be merry, for tomorrow we die."
In other words, action is futile. The product: paralysis.
Might as well go along with the status quo... enriching the current crop
of oil barons. They can't take it with them either, so it doesn't
matter. Does it?
Well, yes. It does.
To avoid paralysis, it's essential to notice that the conclusion is
only valid given the premises. Minor premises are that there are
no low-energy or renewable substitutes for steel and concrete, but the
key premise in this case is that biomass (in the form of wood) is the
best sustainable power source for a post-fossil society.
I'm going to take Stanton's key premise and examine it. Is 230
tons of wood per capita per year a reasonable assumption, what would it
take to get its energy equivalent without burning fossil fuel, and how
much land would be required?
Assuming elm wood at 20 million BTU/cord (128 cubic feet), 23% void
space and 35 pounds per cubic foot yields a heat product of ~5800 BTU
per pound or ~3750 kWh per metric ton. 230 tons per capita per
year comes out to 862,500 kWh/capita/year or an energy consumption of
98 kW equivalent. That's average, not peak. This is clearly
a very high number, leading to an extremely pessimistic conclusion.
Is it warranted? The average household in the US uses about
1 kW average, and industrial and commercial uses are only a few times
that. Net consumption of energy by cars and trucks is about 1/5
of total electric generation capacity. It seems reasonable to
set the actual per-capita energy needs of a decent society, not
particularly optimized for efficiency, at 10 kW or less. Boom,
the sustainable population of a wood-burning England rises to something
closer to 20 million. You'd have to stop immigration yesterday, make
sure the NHS doesn't keep old people alive too long and get birth control
to everyone, but none of the under-20's have to go anywhere.
They can even have a few kids.
But is the assumption of a wood-burning England reasonable, even
remotely? I don't believe so. Forests are not particularly
good converters of solar energy to biomass; they use a great deal on
housekeeping. Grasses are certainly better. But is biomass
even among the top contenders? Stanton's productivity figure of
8 dry tons per hectare per year leads to an average power capture of
30,000 kWh/ha/yr or 3.4 kW/ha. This is a pitifully low figure.
If the average house has a footprint of 80 square meters, the roof is
covered with PV cells at 15% efficiency and each square meter receives
an average of 4 kWh of sunlight per day, the roof would produce 48 kWh/day
or an average of 2 kW. A hectare of these roofs would average 250 kW,
or more than 70 times Stanton's assumption. A city-full of solar
roofs could easily be twenty times as productive as Stanton's proposed
energy farms; a hectare could support the complete energy needs of 25
people, and the land Stanton would devote to a hamlet of 100 would be
able to support the energy needs of 7500 people using a mere 10% of
its 3000 hectares - much of which could be met by the light falling on
buildings and roads. (Boom, the sustainable energy production
could support 150 million; food, fiber, materials and crowding would
come into play first.) It is clear that the assumption of
a wood economy is not just unreasonable, it is ridiculous.
Stanton looks at materials as a difficulty; steel and concrete are
big energy-hogs. Well, maybe. If iron oxide is available it
can be reduced using carbon monoxide, which can be made from most
anything carbonaceous; a net consumption of 50 kg/person/year could
be satisfied with roughly the same weight of wood. A
population of 50 million would consume 2.5 million tons, using the
wood grown on 312,000 hectares of tree farms. (Electric reduction
of iron salts to metal would slash this number immensely.)
And steel is not necessarily an essential material; composites made of
carbon or organic fibers (graphite or Kevlar) in organic (epoxy)
binders can replace it for many purposes, including the wind-turbine
blades and towers that Stanton is so certain are non-renewable.
Building materials? Consider structural insulated panels.
A house made of SIP's with 6 inch (~15 cm) foam cores and 5/16 inch
(.8 cm) plywood or OSB skins would use about 11 kg of material per
square meter of wall; a comfy 2 story 200 m^2 house might use about
700 m^2 of panels including floors (but no interior walls), or about
7.7 tons of wood and foam. If all of that material comes from
tree farms, that's about 1 house per hectare per year; if one person
uses 1/80 of a house per year, the housing needs of 50 million people
could be met from 625,000 ha of tree farms. Between steel production
and housing, tree farming would need roughly 1 million ha out of a
total area that Stanton appears to count as 60 million hectares.
Is there cause for such pessimism as Stanton's? I see a renewable
future just as populous as the present, and a whole lot more technological
and dynamic than he seems to. The road there need not and should
not involve any die-offs (warfare against dysfunctional societies bent on
the conquest or destruction of the rest of the world being a possible
exception). It just requires the application of good science and
a lot of cleverness.
Science and cleverness that Stanton and his fellow travellers paint as
futile, and thus not worth the effort.
Which makes their scenario a self-fulfilling prophecy.
What side are they on, anyway?